1. Field of the Invention
This invention relates to a hard-coated chewing gum with xylitol and polyol coatings, having an extended shelf life.
2. Discussion of Related Art
This invention relates to a hard-coated chewing gum in which the hard coating is composed of xylitol and another polyol, having an improved coating quality and extended shelf life.
Specifically, this invention relates to a chewing gum in pellet form, having one or more sequentially added coats of xylitol and another polyol. The hard pellets are prepared by coating a gum core with syrups of xylitol and another polyol. The coated gum has improved coating quality and longer shelf life.
Chewing gums, including pellet chewing gums, are frequently enclosed with hard or soft coatings. Coatings provide an opportunity for the manufacturer to vary product characteristics such as taste, appearance and nutritional value. In recent years, efforts have been devoted to producing sugarless hard coatings for use in chewing gum. Sugarless coatings which have been investigated include coatings containing compounds such as xylitol, sorbitol, mannitol, and hydrogenated starch hydrolysates.
Sugarless xylitol coated pellet gums have become very popular as products are being manufactured in Europe and Canada. The cost of xylitol is quite high, and partial replacement of the xylitol in the coating would be an advantage. Two polyols in the same coating solution cause problems in the coating process, but sequential coating of gum pellets with two solutions, each containing a polyol, one of which is xylitol, was found to be an acceptable process. Parent patent application Ser. No. 07/857,577, filed Mar. 26, 1992, by Ree and Orr, taught sequential coating with a combination of hydrogenated isomaltulose and xylitol.
U.S. Pat. No. 4,792,453, issued Dec. 20, 1988, to Michael A. Reed, Mansukh M. Patel and Vasek J. Kures, discloses a chewing gum having a sugarless chewing gum center coated with a syrup containing hydrogenated isomaltulose. The sugarless center may include various constituents such as water, an insoluble gum base, a bulking agent, a softener, an artificial sweetener, and a flavoring agent. The sugarless chewing gum center of the reference has a water content of less than about 2.5 weight percent, preferably less than about 1.5 weight percent and most preferably less than about 1.0 weight percent. The use of a center having a low water content, is intended to prevent or reduce the tendency of the gum center from being a water donor to the hard coating.
Sugarless gums coated with hydrogenated isomaltulose-containing syrup possess excellent appearance, taste, texture, mouth feel, and other desirable properties of hard coated chewing gums. Also, it has been found that the relatively anhydrous gum center has the capability of pulling moisture from the hydrogenated isomaltulose-containing coating, causing the coating to exhibit superior hardness. This moisture-pulling from the gum center is attributable, in large part, to the use of glycerin as a softener in the gum center. The moisture-pulling effect is the most pronounced in hard coated chewing gums which contain moderate or relatively high amounts of glycerin in the chewing gum center, on the order of from about 5 to about 15 percent by weight of the chewing gum center.
The tendency of glycerin to pull moisture from the hydrogenated isomaltulose-containing coating can operate as a disadvantage in certain pellet-shaped hard coated chewing gums which, due to their shape, are difficult to isolate from a moisture-containing environment by packaging. For example, pellet gum which is shaped like pillows is difficult to protect from moisture because it is difficult to form a good quality, low or non-moisture permeable package which is suitable for these pellets.
Hydrogenated isomaltulose is a monohydrate. If a hydrogenated isomaltulose-containing coating on a pellet gum becomes too dry, e.g. due to the presence of glycerin, the coating becomes more hygroscopic and absorbs moisture from the surrounding atmosphere. This continuous drying and absorption of moisture from the atmosphere reduces the shelf life of the pellet gum by causing the coating to soften and lose its desirable texture, appearance and mouth feel. Thus, the coating itself must be sufficiently shelf stable against moisture absorption so as not to allow the coating to deteriorate during its shelf life.
Commonly assigned U.S. patent application Ser. No. 07/855,251, filed Mar. 23, 1992, by Michael A. Reed and Jeffrey S. Hook, entitled HARD COATED GUM WITH IMPROVED SHELF LIFE, discloses a chewing gum in pellet form which includes a center portion and an outer coating which contains hydrogenated isomaltulose.
Coating with xylitol is described in U.S. Pat. No. 4,105,801, issued Aug. 8, 1978, to Dogliotti; U.S. Pat. No. 4,127,677, issued Nov. 28, 1978, to Fronczowski et al.; U.S. Pat. No. 4,146,653, issued Mar. 27, 1979, to Mader et al.; U.S. Pat. No. 4,681,766, issued Jul. 21, 1987, to Huzinec et al., U.S. Pat. No. 4,786,511, issued Nov. 22, 1988, also to Huzinec et al.; and U.S. Pat. No. 4,828,845, issued May 9, 1989, to Zamudio-Tena et al.
Patents and publications which discuss lactitol include U.S. Pat. No. 3,973,050, issued Aug. 3, 1976, to Hayashibara et al. (foods and drinks containing lactitol as a sweetener); U.S. Pat. No. 4,973,486, issued Nov. 27, 1990, to Matsumoto et al. (formulation of lactitol-containing food); and U.S. Pat. No. 4,999,058, issued Mar. 12, 1991, and U.S. Pat. No. 5,160,546, issued Nov. 3, 1992, both to Kawashima et al. (production of lactitol trihydrate; use in chewing gum, column 6 of each patent); British Patent 1,252,300, Hayashibara, published Nov. 10, 1971 (food materials containing lactitol); PCT published Patent Applications WO 90/06317, published Jun. 14, 1990, and WO 92/16542, published Oct. 1, 1992, both in the names of Heikkila et al. (preparation of crystalline lactitol and use as sweetening agent; use in chewing gums mentioned at page 1, lines 10-11 of '317 and page 5, line 13 of '542); Ir. I. H. Blankers, PURAC biochem b.v., LACTY.RTM.-- A UNIQUE REDUCED CALORIE SWEETENER (October, 1992); CCA biochem b.v., Application Information, Hard Panned Chewing Gum (undated, 1 page); CCA biochem b.v., Application Information, Starting Point Formulation for a Lacty.RTM.-containing Chocolate and Chewing Gum (undated, 1 page); CCA biochem b.v., INTERNATIONAL APPROVAL SITUATION FOR LACTITOL (1988) (1 page); CCA biochem b.v., LACTY.RTM./A NEW REDUCED CALORIE SWEETENER (undated) (page 5, use in chewing gum); CCA biochem b.v., Product Data, LACTY.RTM.-M (undated, 1 page); Ir. C. H. den Uijl, CCA biochem b.v., LACTY.RTM., PROPERTIES AND APPLICATIONS OF THIS NEW REDUCED CALORIE SWEETENER (1987); (anon.) Lacty.RTM., A New Bulk Sweetener, CONFECTIONERY PRODUCTION, p. 656 (September 1990); PURAC blochem, LACTY.RTM. CONTAINING CHEWING GUM (undated, 1 page); and PURAC blochem, LACTY.RTM./A UNIQUE REDUCED CALORIE SWEETENER (undated) (page 5, use in chewing gum).
Patents and publications which discuss maltitol include U.S. Pat. No. 4,556,565, issued Dec. 3, 1985, to Arima et al. (sweetening compositions comprising maltitol); U.S. Pat. No. 4,623,543, issued Nov. 18, 1986, to Motegi et al. (non-hygroscopic candies containing maltitol); U.S. Pat. No. 4,717,765, issued Jan. 5, 1988, to Hirao et al. (production and use of maltitol anhydrous crystals; used in chewing gum in Example 12 in column 13); U.S. Pat. No. 4,840,797, issued Jun. 20, 1989, to Boursier (maltitol coating); U.S. Pat. No. 4,933,188, issued Jun. 12, 1990, to Cherukuri et al. (maltitol sweetening/bulking agent); U.S. Pat. No. 4,959,225, issued Sep. 25, 1990, to Wong et al. (sweetening compositions comprising maltitol); and U.S. Pat. No. 5,120,551, issued Jun. 9, 1992, to Yatka et al. (maltitol syrup); European Patent Publication 0,390,299, published Oct. 10, 1990, in the names of Bakal et al. (foodstuffs containing maltitol); and Japanese Patent Publications 53 (1978)--127,858, published Nov. 8, 1978 in the names of Fukuda et al. (chewing gum which may include maltitol) and 4 (1992)--287,659, published Oct. 13, 1992, in the names of Shigeni et al. (low-calorie sweetener containing maltitol).
Other patents and publications which may be of interest include U.S. Pat. No. 5,017,400, issued May 21, 1991, to Olinger et al. (non-cariogenic sweetener containing xylitol and maltitol; used in chewing gums, see Example I in columns 5-6); U.S. Pat. No. 5,135,761, issued Aug. 4, 1992, to Dave et al. (coated chewing gum with emulsifier subcoat); U.S. Pat. No. 5,144,024, issued Sep. 1, 1992, to Pepper et al. (shelf stable liquid xylitol compositions comprising non-xylitol polyols such as maltitol); U.S. Pat. No. 5,171,589, issued Dec. 15, 1992, to Richey et al. (coated chewing gum polished with colored wax); and PCT published Patent Application WO 91/07100, published May 30, 1991, in the names of Oravainen et al. (hard candy containing xylitol and optionally maltitol or lactitol). See also PCT Patent Application PCT/US92/11195, filed Dec. 23, 1992, in the names of Yatka et al., to be published about June, 1994 (chewing gum containing lactitol).